ST.-DENIS, France — The French police stormed an apartment in the medieval heart of the northern Paris suburb of St.-Denis early Wednesday morning, in an attempt to find the Belgian man suspected of orchestrating the Paris terrorist attacks. Two people died in the raid, including a young woman who detonated an explosive vest, and seven people were arrested. It was not clear if the suspect was there.
“It is currently impossible to give you the identities of the people who were arrested, which are being verified,” the Paris prosecutor, François Molins, told reporters after the raid. “Everything will be done to determine who is who.”
The raid began around 4:15 a.m., when special police forces, backed by truckloads of soldiers, cordoned off an area near the Place Jean Jaurès, a main square in St.-Denis not far from the Stade de France, where three of the seven attackers who died on Friday night blew themselves up.
A total of seven people were arrested: three in the apartment, two who were found “hiding in the rubble,” and two more outside the apartment.
The target of the operation was Abdelhamid Abaaoud, the Belgian militant who is thought to have organized the attacks.
The police operation unfolded over nearly seven hours, with an initial series of explosions followed by sporadic bursts of gunfire. A government spokesman declared the operation over on Twitter at 11:47 a.m. Five police officers were lightly wounded, and a 7-year-old police dog, a Malinois named Diesel, was killed.
Interior Minister Bernard Cazeneuve said the 110 police officers involved had been “extremely brave” during the operation, “enduring gunfire for many hours, in conditions that they never encountered up until now.” He also praised the inhabitants of St.-Denis for their calm.
St.-Denis, a city of 118,000 people, is known for its melting-pot population and large Muslim community, as well as a Gothic basilica where many French monarchs are buried. Toward the end of the raid, the police broke through the door of a smaller church, St.-Denys de l’Estrée, for reasons that were not immediately clear.
Djamila Khaldi, a 54-year-old cashier who lives near the basilica, was preparing to take her daughter to the airport when the gunfire erupted.
Ms. Khaldi said was not surprised the police had tracked the suspects to the neighborhood. She said a friend of hers believed she had seen one of the wanted men, Salah Abdeslam, on Monday. “She was terrified and she looked at another woman knowing that she recognized him too,” Ms. Khaldi said. “They did not dare to go to the police.”
Didier Paillard, the mayor of St.-Denis, said the Rue du Corbillon, where the raid occurred, had “many buildings and habitats in a disgraceful state,” with some apartments lacking even electricity and running water. “We were not prepared for this discovery,” he said of the raid. “This is a city that has 130 different nationalities, including people who come from war zones. We are a population that needs serenity.”
Mr. Abdeslam was thought to have escaped to Brussels after the attacks, which killed 129 people. He has been the subject of an intense international manhunt, along with a second suspect. It was not immediately clear on Wednesday morning if that suspect was Mr. Abaaoud, or if the police were instead seeking three men: Mr. Abdeslam, Mr. Abaaoud and yet another man.
French and American intelligence officials had said on Tuesday they believed that Mr. Abaaoud was in Syria with fellow Islamic State militants.
French media outlets reported that the location of the suspected hide-out in St.-Denis was gleaned from one of the attackers’ cellphones, which was found in a trash bin near the Bataclan concert hall, where 89 people died on Friday.
A man arrested during the police operation on Wednesday later told Agence France-Presse that he had lent the apartment to the men as a favor to a friend. “I said that there was no mattress, they told me, ‘It’s not a problem,’ they just wanted water and to pray,” the man said before being handcuffed and led away by the police.
Mr. Cazeneuve, Prime Minister Manuel Valls, Defense Minister Jean-Yves Le Drian and Justice Minister Christiane Taubira joined President François Hollande at the Élysée Palace to monitor the operation.
Some of the attackers in the Friday night attacks rented a house in the northeast Paris suburb of Bobigny last week, telling the landlady they were businessmen from Belgium, and a hotel suite in the southeast Paris suburb of Alfortville, officials said.
France conducted another series of airstrikes late Tuesday and into Wednesday in Raqqa, Syria, the stronghold of the Islamic State. More than 25 explosions struck Raqqa late Wednesday, according to the Syrian Observatory for Human Rights, a monitoring group in Britain that has a network of contacts in Syria.
Many of the strikes hit deserted areas that had already been struck before; but there were also casualties reported, in addition to property damage, the observatory said.
France, through its defense minister, Mr. Le Drian, took the extraordinary step on Tuesday of invoking a European Union treaty that obliges members to help any member that is “the victim of armed aggression on its territory.”
Mr. Hollande took steps to shore up global support for what he has called a war to annihilate the Islamic State, also known as ISIS or ISIL. He met with Secretary of State John Kerry, who expressed sympathy but reiterated the Obama administration’s view that the group would not be destroyed until Syria’s embattled president, Bashar al-Assad, relinquishes power.
Mr. Hollande will visit Washington and Moscow next week to meet with Mr. Obama and the Russian president, Vladimir V. Putin. In Britain, Prime Minister David Cameron told Parliament that the Paris attacks had strengthened the case for intervening against the Islamic State in Syria, a move that Parliament rejected in 2013.
On Tuesday, France’s third and final day of national mourning, crowds gathered to light candles and lay flowers at the Place de la République and at makeshift memorials at the sites of the attacks. In the southwestern city of Toulouse, thousands gathered in the central square, waving French flags and singing “La Marseillaise,” the national anthem.
“The terrorists want to erase everything: culture, youth, life, and also history and memory,” Mr. Hollande said in a speech at a Unesco conference in Paris.
“You do not fight against terrorism by hiding, by putting your life on hold, by suspending economic, social and cultural life, by banning concerts, theater, sports competitions,” he said. “We will not yield to terrorism by suspending our way of life.”
Many Parisians and visitors followed his advice, flocking to restaurants, cafes and museums. But the country continued to reel from the attacks, the worst violence on French soil in decades. Officials said the bodies of 117 of the 129 people killed had been positively identified; 221 of the 352 people injured remained in hospitals, or which 57 were in intensive care.
The country remained under a state of emergency, as developments in the investigation emerged in a steady trickle.
On Tuesday morning, the authorities seized a black Renault Clio with Belgian license plates in the 18th Arrondissement on the northern edge of Paris, next to the suburb of St.-Denis, where three suicide bombers detonated their explosives during a soccer game at the Stade de France. The authorities are looking into the possibility that the vehicle might have been intended for yet another attack.